Freeze and Frost Protection with Aqueous Foam— Field Experiments

Abstract

<jats:p>Newly formulated aqueous foam was tested in the field. The foam demonstrated the longevity necessary for practical field use. Soil temperatures beneath an insulation layer of aqueous foam were measured to determine the effectiveness of foam as soil mulch. Leaf temperature within a canopy was monitored to observe the modification of plant leaf temperature, and to evaluate the phytotoxic effects of foam applied directly to the leaf canopy. Leaves were not damaged after being covered with the foam for two weeks. The foam-protected soil was effectively insulated, and the aqueous foam proved to be an effective radiation shield against the cold night sky. Temperature differences as high as 5 °C (9 °F) were measured between the foam-covered and uncovered copper metal plates, which were used to simulate plant leaves. The foam covered plates were ≈80% as effective as the aluminum foil covered plates in reducing radiation heat transfer.</jats:p>

Freeze and Frost Protection with Aqueous Foam— Foam Development

“…It is interesting that the slopes for both cases were nearly linear after the first 5 h in a semilog graph. It is assumed that evaporation by advection was initially active on the surface, and that constant diffu- sion process took place after the first 5 h. The remaining water was important for frost protection, based on the experimental data discussed by Choi and Giacomelli (1999).…”

“…In the present paper, the experimental design and the qualitative evaluation of the foam properties will be described. The measurements and results of soil and plant temperature changes under the foam is discussed in the subsequent paper (Choi and Giacomelli, 1999).…”

“…The major properties of the newly developed foam include: long term stability, biode-gradability, adherence to plant canopy during application, and nontoxicity to plant or environment. Ability to serve as a conduction, convection and radiation barrier against freeze or frost protection is considered by Choi and Giacomelli (1999). A mechanism for large-scale field application of the developed foam has yet to be developed.…”

“…In the present paper, the development and evaluation of long-lasting foam will be discussed in detail. In the paper by Choi and Giacomelli (1999), the results of field experiments involving freeze and frost protection are presented.…”

Internal freezing and heat loss of apple (Malus domestica Borkh.) and sweet cherry (Prunus avium L.) reproductive buds are decreased with cellulose nanocrystal dispersions

“…Insulative aqueous foams have been tested extensively since the 1960s ( Braud and Chesness, 1970 ). Multiple formulations of low thermal conductivity foams have been shown to create an insulative barrier in low-growing crops such as lettuce and strawberries, offering up to 9°C protection ( Choi and Giacomelli, 1999 ; Choi et al., 1999 ). However, because of application and durability constraints, these materials are best suited for low-growing crops and have not been used effectively in trees ( Bartholic, 1985 ; Choi et al., 1999 ).…”